“双保”型改性天然高分子基钻井液技术  

A modified natural polymer drilling fluid for both oil/gas reservoir protection and environment control

作　　者：史鸿祥[1] 杜晓勇[1] 商勇[1] 张民立 

机构地区：[1]塔里木油田分公司 [2]塔里木勘探四公司

出　　处：《钻井液与完井液》2004年第6期28-30,共3页Drilling Fluid & Completion Fluid

摘　　要：为解决轮古地区井径扩大率偏高、潜山地层顶部界面难于测准等难题 ,也为同时实现对油气层及环境的保护 ,研究开发了“双保”型改性天然高分子基钻井液体系 ,合成了该体系所需处理剂 ,包括天然高分子包被剂IND30、天然高分子降滤失剂NAT2 0、无荧光白沥青NFA 2 5和聚合醇PGCS 1。评价了该体系的基本性能和抗温、抗污染能力 ,在 3口直井和 2口水平井中进行了应用试验。应用结果表明 ,该钻井液性能稳定 ,流变性独特 ,粘度和切力低 ,起下钻畅通 ,钻头、钻具无泥包现象 ;井壁稳定 ,无垮塌、掉块现象 ;抑制性强 ,返出钻屑棱角分明 ,代表性极好 ,同时具有良好的润滑性 ;“双保”型改性天然高分子基钻井液性能 ,不但优于常规聚磺钻井液 ,而且优于环保A体系 ,处理剂消耗数量及使用品种大大减少 ,使分析问题、找原因及维护、处理简单化。该体系单个处理剂EC50 值均大于 30 0 0 0mg/L ,现场井浆EC50 值大于 10 0 0 0 0mg/L ,达到可排放标准 ;同时渗透率恢复值大于 90 % ,表明其有良好的保护油气层特性 ;该钻井液所用材料无荧光 ;体系无油、无腐蚀 ,设备卫生清洁。In Lungu area of Xinjiang oilfield, problems such as high well enlargement rate and difficult to detect the top interface of the Buried hill formation exist. To realize protecti MNon for both the oil/gas reservoir and the environment, a modified natural polymer drilling fluid exhibiting protecting function for both aspects was developed. The necessary additives were studied, which includes natural high molecule enveloping agent IND30 and filtrate reducer NAT20, non-fluorescence white alphalt NFA-25 and polycol PGCS1. Fundamental properties of the fluid and its thermal stability and anti-pollution ability were evaluated.The fluid was applied in 3 vertical wells and 2 horizontal wells, and onsite using showed that the fluid hasadvantages as follows. (1) stable property, particular theological property, low viscosity and shear forcevalue. The trip went well with no bit balling; and the well wall was in good condition with no sloughing;(2) strong inhibition. The cuttings were in clear shape; (3) excellent lubrication. Properties of the fluidare not only superior to that of the conventional polysulfonate drilling fluid, but also better than those of the environment friendly A drilling fluid system. The necessary additives' volume and number were dramatically decreased, simplifying the analyzing, studying the causes, making maintenance and conditioning process easier. What's more, the individual additive in this fluid system has EC 50 value of more than 3000mg/L, and the same parameter of the field fluid was more than 100000 rag/L, which qualified the fluid tobe discharged safely. The permeability recovery percentage was more than 90%, and all the materials in this fluid are non-fluorescence. In addition, with no oil in the fluid, there is no corrosion to the clean equipments.

关 键 词：钻井液技术 钻井液性能 处理剂 保护油气层 井径扩大 抗温 轮古地区 改性 天然高分子 用材 

分 类 号：TE254[石油与天然气工程—油气井工程] TE28